The present invention is directed to colorant compounds. More specifically, the present invention is directed to colorant compounds particularly suitable for use in hot melt or phase change inks.
Of background interest to the present invention are the following documents, the disclosures of each of which are totally incorporated herein by reference: GB 2 311 075; Zh. Organ. Khim. (1965), 1(3), 584-6; Zh. Obsch. Khim. (1964), 34(6), 2041-4; Zh. Obsch. Khim. (1964), 34(6), 2039-41; Zh. Obsch. Khim. (1964), 34(2), 640-44; Zh. Obsch. Khim. (1963), 33(12), 3943-6; Zh. Obsch. Khim. (1963), 33(4), 1089-92; Zh. Obsch. Khim. (1962), 32, 1489-92; Zh. Obsch. Khim. (1962), 32, 1485-9; Zh. Obsch. Khim. (1962), 32, 1480-5; Zh. Obsch. Khim. (1962), 32, 1477-80; Zh. Organ. Khim. (1970), 6 (2), 369-71; Zh. Organ. Khim. (1972), 8(8), 1726-9; Zh. Org. Khim. (1966), 2(9), 1721; Zh. Organ. Khim. (1966), 2(5), 927-31; Journal of Fluorescence, Vol. 2, No. 3, pp. 93-98 (1992); U.S. Pat. No. 1,991,482; U.S. Pat. No. 5,847,162; U.S. Pat. No. 4,935,059; U.S. Pat. No. 4,647,675; U.S. Pat. No. 1,981,515; U.S. Pat. No. 1,981,516; GB 421 737; JP61221265; U.S. Pat. No. 5,084,099; U.S. Pat. No. 5,507,864; U.S. Pat. No. 5,621,022; U.S. Pat. No. 5,747,554; U.S. Pat. No. 5,902,841; EP-0 565 798; U.S. Pat. No. 5,496,879; DE 4205636AL; DE 4205713AL; U.S. Pat. No. 4,889,560; U.S. Pat. No. 4,889,761; U.S. Pat. No. 5,372,852; U.S. Pat. No. 5,221,335; U.S. Pat. No. 5,621,022; U.S. Pat. No. 3,653,932; U.S. Pat. No. 4,390,369; U.S. Pat. No. 4,484,948; U.S. Pat. No. 4,684,956; U.S. Pat. No. 4,851,045; U.S. Pat. No. 4,889,560; U.S. Pat. No. 5,006,170; U.S. Pat. No. 5,151,120; U.S. Pat. No. 5,372,852; U.S. Pat. No. 5,496,879; EP-0187352; EP-0206286; DE 4205636AL; DE 4205713AL; WO 94/04619.
While known compositions and processes are suitable for their intended purposes, a need remains for new magenta colorant compositions. In addition, a need remains for magenta colorant compositions particularly suitable for use in phase change inks. Further, a need remains for magenta colorants with desirable thermal stability. Additionally, a need remains for magenta colorants that exhibit minimal undesirable discoloration when exposed to elevated temperatures. There is also a need for magenta colorants that exhibit a desirable brilliance. In addition, there is a need for magenta colorants that exhibit a desirable hue. Further, there is a need for magenta colorants that are of desirable chroma. Additionally, there is a need for magenta colorants that have desirably high lightfastness characteristics. A need also remains for magenta colorants that have a desirably pleasing color. In addition, a need remains for magenta colorants that exhibit desirable solubility characteristics in phase change ink carrier compositions. Further, a need remains for magenta colorants that enable phase change inks to be jetted at temperatures of over 135° C. while maintaining thermal stability. Additionally, a need remains for magenta colorants that enable phase change inks that generate images with low pile height. There is also a need for magenta colorants that enable phase change inks that generate images that approach lithographic thin image quality. In addition, there is a need for magenta colorants that exhibit oxidative stability. Further, there is a need for magenta colorants that do not precipitate from phase change ink carriers. Additionally, there is a need for magenta colorants that do not, when included in phase change inks, diffuse into adjacently printed inks of different colors. A need also remains for magenta colorants that do not leach from media such as phase change ink carriers into tape adhesives, paper, or the like. In addition, a need remains for magenta colorants that, when incorporated into phase change inks, do not lead to clogging of a phase change ink jet printhead. Further, there is a need for magenta colorants that enable phase change inks that generate images with sharp edges that remain sharp over time. Additionally, there is a need for magenta colorants that enable phase change inks that generate images which retain their high image quality in warm climates. Further, there is a need for magenta colorants that enable phase change inks that generate images of desirably high optical density. Additionally, there is a need for magenta colorants that, because of their good solubility in phase change ink carriers, enable the generation of images of low pile height without the loss of desirably high optical density. A need also remains for magenta colorants that enable cost-effective inks. In addition, a need remains for magenta colorants that are compounds having metal compounds associated with chromogens, wherein the thermal stability of the metal compound colorants exceeds that of the chromogens unassociated with a metal.